1. Field of the Invention
The present invention relates to automatic cleaning apparatus for paint sprayer gun, and more particularly, to an cleaning apparatus for paint sprayer gun which employs compressed air as its power source so as to eliminate hazardous electrostatic induction owing to mechanical friction caused by rotation of apparatus components during the cleaning operation, Accordingly, the cleaning apparatus has noticeable advantages of low noise, simple structure, high security, prolonged lifetime, high flexibility and low production cost.
2. Description of the Prior Art
In a conventional paint sprayer gun, it is normally composed of a gun body, a nozzle, and a paint container, and the nozzle further includes various components such as a nozzle tube, an air inlet collar etc. This causes that the paint sprayer gun must be cleaned after use so as to remove undesired remainder of paint in the component parts of the gun thereby preventing degrading performance of the paint sprayer gun, or mingling the paint color by remaining paint with the new one. Accordingly there has appeared an automatic cleaning apparatus for paint sprayer gun specially for cleaning up each component part of the apparatus.
Incidentally, a conventional cleaning apparatus employs an air compressor associated with a pump as its power source. This causes the conventional cleaning apparatus has to operate with a high cost and high noise. Moreover, the way of motion, such as rotation and reciprocation (pump motion) that the conventional cleaning apparatus relies on is apt to cause explosion of cleaning solvent (such as benzene) contained in the apparatus owing to electrostatic induction induced by mechanical friction thereof.
Aiming at the above depicted defects, the present inventor is to propose a newly developed automatic cleaning apparatus for paint sprayer gun simply constructed with a low production cost, and capable of operating at low noise, high security and prolonged lifetime.
It is an object of the present invention to provide an automatic cleaning apparatus for paint sprayer gun which comprises a solvent cleaning tank with a compressed air inlet at one side, and a cleaning tank having a plurality of vertical different length first tubes. At least a nozzle is provided at one end of each first tube, and all the other ends of the first tubes are connected together to a second tube. A third tube is connected to the second tube at a proper position thereof. The other end of the third tube is appropriately inserted into the solvent cleaning tank such that the pressurized air is able to enter the solvent cleaning tank thereof from the air inlet and force the solvent to go through the other opening end of the third pipe and is ejected from the individual nozzles. Besides, an entrainer is provided in the cleaning tank, and a plurality of through holes are formed on the board surface of the entrainer and communicating with the nozzles of the first tubes to accept the solvent cleaned out from the component parts of each paint sprayer gun placed in the cleaning tank. Moreover, a check valve is installed at a proper position between the cleaning tank and the solvent cleaning tank for collecting the solvent to flow back to the solvent cleaning tank. In this version, those shortcomings inherent to the conventional techniques described above can be eliminated by the present invention employing compressed air as the power source for cleaning.
It is another object of the present invention to provide an automatic cleaning apparatus for paint sprayer gun, wherein the compressed air inlet has a safety valve and a time counter such that the time counter is able to indicate the safety valve to interrupt the entry of the compressed air from the inlet after air pressure has reached to a prescribed value. Besides, an upper lid is provided for the cleaning tank and a micro switch capable of detecting the air pressure is installed at one corner side of the lid. As soon as the lid is lifted up, the micro switch is actuated to interrupt entry of the compressed air from the inlet so that the nozzles can not eject the solvent thereby protecting the operator securely from being hurt by ejected solvent.